Orthoses for joint rehabilitation

ABSTRACT

Orthoses with microprocessor control placed around the joint of a patient are used to perform and to monitor isometric, range-of-motion, proprioception and isotonic exercises of the joint. A variety of improved hardware elements result in an orthosis that is easier to use and interacts more efficiently with the controller to allow the monitoring of a greater range of motions while holding down cost and provide suitable accurate evaluation of the exercises. Efficient ways of programming the exercises, monitoring the exercises and evaluating the exercise provide a comprehensive program for the rehabilitation of an injured or weakened joint.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 60/098,779, entitled “ORTHOSIS FOR JOINT REHABILITATION,” filed onSep. 1, 1998.

BACKGROUND OF THE INVENTION

The invention relates to orthosis useful for the rehabilitation ofinjured and/or weakened joints.

Both muscles and bones should be exercised to maintain strength. Also,bone fractures that are exposed to permissible weight bearing stressoften heal more predictably and more rapidly than fractures that are notstressed at all. Improved healing based on application of appropriatestress is also believed to be true for connective tissue, such asligaments and certain cartilage.

Suitable stress can be applied to the tissue by the performance ofselected exercises. For example, isometric exercise generally involvesthe exertion of force against a relatively immovable object, whichallows no motion of the limb. To perform isometric exercises, arestraining device can be used that has a substantially unchangingposition for the duration of a particular exercise routine. Isotonicexercises involve exertion against the same weight or resistance througha range of motion. Isokinetic exercise is designed to mimic exertionsthat take place on a playing field or the like. When performingisokinetic exercises in a simulated environment, a machine is used toprovide resistance in direct proportion to the exertion of theexerciser.

Isometric exercises are particularly useful with painful injuries tolower the risk of further injury. Also, because isometric exercises areperformed in a static position, they allow very position specifictherapy. For example, to climb stairs, a person needs more strength atan approximate 60° knee bend, when combined with the hip and anklejoints. Therefore, the isometric exercises can be designed to focus onthe strengthening of a joint at optimum angles where additional strengthis needed. If performed in a controlled manner, isometric exercises canbe performed earlier in the recuperation period to speed recovery. Asthe patient's recovery progresses, isotonic exercises or other exercisescan be used to reestablish a desired strength through a range of motionabout a joint. As recovery progresses eventually the patient is able toperform a full range of exercises.

A difficulty with application of stress to an injured joint include arisk of inappropriately timed or excessive stress. This can impairhealing and/or further injure the damaged tissues. Thus, exercises needto be carefully planned to provide appropriate amounts of stress. Also,the performance of the exercises should be monitored closely to reducethe risk of injury. Moreover, the need to carefully plan and closelymonitor the exercises provides a cost and motivation barrier toaccessing desirable amounts of exercise.

SUMMARY OF THE INVENTION

In a first aspect, the invention pertains to an orthosis comprising:

-   -   a first support portion that fits around a first body portion on        a first side of a patient's joint;    -   a second support portion that fits around a second body portion,        the second body portion being on the opposite side of the joint        from the first body portion;    -   a hinge connecting the first support portion and the second        support portion; and    -   a resistance applicator connected to the hinge to provide        resistance to rotation of the hinge, the resistance applicator        comprising:        -   a first surface;        -   a second surface generally parallel to the first surface and            selectively movable relative to the first surface;        -   a crank that is located between the first surface and second            surface and that is rotatable relative the first surface;            and        -   a compression unit located between the first surface and the            second surface, the compression unit applying resistance            with respect to the rotation of the crank relative to the            first surface with the amount of resistance being related to            the distance of the first surface to the second surface.            The first body portion and the second body portion can be            connected by way of a plurality of joints. The compression            unit can include a plurality of crank rings interspersed            with and in frictional contact with a plurality of housing            rings, where the crank rings rotate with the crank and the            housing rings rotate with the first surface.

In another aspect, the invention pertains to an orthosis comprising:

-   -   a first support portion that fits around a first body portion on        a first side of a patient's joint;    -   a second support portion that fits around a second body portion,        the second body portion being on the opposite side of the joint        from the first body portion;    -   a hinge connecting the first support portion and the second        support portion; and    -   a resistance applicator applying selective resistance to        rotation about the hinge;    -   a strain sensor operably connected to the first support portion;        and    -   a controller calibrated to measure the force applied to rotate        the hinge using the electrical resistance of the strain sensor.        In preferred embodiments, the controller includes a digital        microprocessor.

Moreover, the invention pertains to a method of performing closed chainexercises, the method comprising:

-   -   applying force against a force transducer with a repetition rate        and force target specified with a digital microprocessor-based        portable controller, the force transducer being held fixed in        space by forces external to the patient;    -   measuring the force applied to the force transducer using the        controller, the controller being operably connected to the force        transducer; and    -   displaying the force applied to the force transducer.        The digital microprocessor can be used to calculate relative        forces within the physiological tissue of the patient.

In a further aspect, the invention features a method of performingcoordination exercises for neuromotor training comprising:

-   -   flexing a joint such that a cursor on a display moves to reach a        target position on the display at a selected, prescribed time,        the motion of the cursor being correlated with the motion or        strain of the joint by way of a sensor in an orthosis placed        around the joint.        In some embodiments, the orthosis comprises:    -   a first support portion that fits around a first body portion on        a first side of the joint;    -   a second support portion that fits around a second body portion,        the second body portion being on the opposite side of the joint        from the first body portion;    -   a flexible connection connecting the first support portion and        the second support portion;    -   a position sensor operably connected to the flexible connection        such that the position sensor detects the relative orientation        of the first support portions with respect to the second support        portion.        The position sensor can be operably connected to a controller,        preferably with a digital microprocessors. Alternatively, lower        cost analog decision array with resistor networks connected to a        meter, light bank or audible output feedback could be used. A        suitable analog controller for this purpose is an LM3914        integrated circuit LED driver.

Moreover, the invention pertains to an instrumented exercise devicecomprising:

-   -   an elastic cord;    -   a transducer connected to the elastic cord such that forces        applied to the cord alter output from the transducer; and    -   a display operably connected to the transducer.        The transducer and display can be connected to a digital        microprocessor. The microprocessor can further be used to        perform calculations and statistical analyses based on the        output of the transducer.

Furthermore, the invention pertains to an instrumented exercise devicecomprising:

-   -   a frame comprising two lever arms connected at a joint;    -   a transducer connected to the frame such that torsional forces        applied against the frame are measured by the transducer; and    -   a display operably connected to the transducer.

In a further aspect, the invention pertains to a kit comprising:

-   -   two hinges;    -   two frame elements extending from each hinge such that relative        motion of the frame elements extending from one of the hinges        rotates that hinge;    -   four sleeves where the sleeve receives and holds fast a frame        element, where each sleeve attaches to a body part cover;    -   a strain sensor connected to a frame member; and    -   a controller that displays a reading related to the strain        measured by the strain sensor.        The controller can include a microprocessor. The sleeves can        releasably hold a corresponding frame element. Alternatively,        the sleeves can irreversibly hold a corresponding frame element        and wherein the sleeve can be cut without damaging the frame        element.

Additionally, the invention pertains to an orthosis comprising:

-   -   a hinge;    -   two frame elements extending from the hinge such that relative        motion of the frame elements extending from the hinge rotates        the hinge;    -   two sleeves, where a sleeve receives and holds fast a frame        element;    -   two disposable rigid body part covers, one body part cover        fitting over a body part on one side of a patient's joint and        the second body part cover fitting over a body part on the        second side of a patient's joint;    -   a strain sensor connected to a frame member; and    -   a controller that displays an output related to the strain        measured by the strain sensor.

Moreover, the invention pertains to an orthosis comprising:

-   -   a first support portion that fits around a first body portion on        a first side of a patient's joint;    -   a second support portion that fits around a second body portion,        the second body portion being on the opposite side of the joint        from the first body portion; and    -   a hinge connecting the first support portion and the second        support portion, the hinge having a locking mechanism that is        released by depressing a button.        The orthosis can further include a slide member that can        releasably hold the button in the depressed, unlocked position.

In addition, the invention pertains to an orthosis comprising:

-   -   a first support portion that fits around a first body portion on        a first side of a patient's joint;    -   a second support portion that fits around a second body portion,        the second body portion being on the opposite side of the joint        from the first body portion;    -   a flexible connection connecting the first support portion and        the second support portion; and    -   a securing cuff connected to one of the support portions, where        the securing cuff can be reversibly tightened around the        corresponding body portion at a narrowing section of the        skeletal system to inhibit the motion of the support portions        relative to the body portions.

In another aspect, the invention pertains to a strain measuring circuitcomprising:

-   -   a strain sensor;    -   a signal conditioner that biases the strain sensor with a known        voltage and amplifies the biased signal so that the variable        resistance of the strain sensor due to applied stress is output        as an analog signal;    -   an analog-to-digital converter receiving the output of the        signal conditioner;    -   a digital processor that receives the output of the        analog-to-digital converter and that evaluates the error of the        strain measurement based on the precision of the        analog-to-digital converter and the properties of the signal        conditioner to set an output signal to a digital-to-analog        converter to adjust the reference of the strain measurement to        bring the error of the measurement to within tolerance values;        and    -   a digital-to-analog converter receiving a digital output from        the digital processor and outputting an analog signal as a        reference signal to the signal conditioner.

Furthermore, the invention pertains to a method of calibrating a strainmeasurement comprising:

-   -   incorporating a strain sensor into a summing amplifier circuit,        where the summing amplifier circuit performs the amplification        based on a value input from a digital-to-analog converter;    -   digitizing the output of the summing amplifier circuit using an        analog-to-digital convertor;    -   estimating the error of the strain measurement based on the        number of bits of the output of the analog-to-digital convertor        and the gain of the amplifier circuit;    -   determining if the estimate error is within tolerance values;        and    -   altering the output to the digital to analog converter if the        error estimate is outside of tolerance values.

In a further aspect, the invention pertains to a joint force applicatorcomprising:

-   -   a force applicator that applies a correction force to a joint        when placed around the joint;    -   a force distributor that distributes the force opposing the        correction force such that the correction force applies a shear        force at the joint to change joint alignment during motion        involving the joint;    -   a force transducer measuring a quantity related to the        correction force; and    -   a processor displaying a value related to the correction force.        The processor can be analog, or the processor can be a digital        processor. The force distributor can comprise a strap, and the        force transducer can comprise a strain sensor operably connected        to the strap. The force transducer can include a pressure sensor        operably connected to the force applicator.

In another aspect, the invention pertains to an orthosis comprising:

-   -   a first support portion that fits around a first body portion on        a first side of a patient's joint;    -   a second support portion that fits around a second body portion,        the second body portion being on the opposite side of the joint        from the first body portion;    -   a flexible connection connecting the first support portion and        the second support portion;    -   a position sensor operably connected to the flexible connection        such that the position sensor detects the relative orientation        of the first support portions with respect to the second support        portion; and    -   and a microprocessor based portable controller connected to the        position sensor,        where the first support portion and the second support portion        each have a connection for attachment to a continuous passive        motion device. The orthosis can further include a continuous        passive motion (CPM) device, the CPM device including a motor        and a frame with matched connectors for attachment to the first        support portion and the second support portion and the frame        being operably connected to the motor such that motion of the        motor moves the frame and moves the first support portion        relative to the second support portion.

In addition, the invention pertains to a method of evaluating anexercise program or the patient's response to the injury comprising:

-   -   prompting responses by the patient to a series of inquiries        using a portable controller; and    -   evaluating the condition of the patient in an exercise program        by examining the responses to the questions.        The prompting of responses to the questions can occur away from        a health care facility. The questions can relate to the pain        felt by the patient.

In another aspect, the invention pertains to a method for programming aportable controller to guide a patient through an exercise routine, themethod comprising:

-   -   downloading a program to the portable controller from a        computer, wherein the program is assembled by the computer based        on exercise parameters entered into the computer by a health        care professional.

In a further aspect, the invention pertains to a monitoring stationcomprising:

-   -   a digital computer programmed to assemble a microprocessor        program for a microprocessor based controller according to        parameters entered into the digital computer upon prompting by        the digital computer; and    -   a port configured to download the microprocessor program to the        controller.

In addition, the invention pertains to an instrumented hinge comprising:

-   -   a first lever arm;    -   a second lever arm;    -   a biaxial hinge connecting the first lever arm and the second        lever arm, the biaxial hinge including a position sensor        providing an output related to the relative orientation of the        first lever arm and the second lever arm, the biaxial hinge        having two coupled rotational axes; and    -   an output device connected to the position sensor of the biaxial        hinge.        The position sensor associated with the biaxial hinge and the        display can be connected to a digital microprocessor. One or        both lever arms connected to the biaxial hinge can include        strain sensors. Also, the instrumented biaxial hinge can be        incorporated into an instrumented orthosis comprising:    -   a first support portion that fits around a first body portion on        a first side of the joint;    -   a second support portion that fits around a second body portion,        the second body portion being on the opposite side of the joint        from the first body portion;    -   a biaxial hinge connecting the first support portion and the        second support portion, the biaxial hinge including a position        sensor providing an output related to the relative orientation        of the first support portion and the second support portion, the        biaxial hinge having two coupled rotational axes; and    -   an output device connected to the position sensor of the biaxial        hinge.

Furthermore, the invention pertains to an orthosis comprising:

-   -   a first support portion designed for external fixation to a body        portion on a first side of a joint;    -   a second support portion designed for external fixation to a        second body portion, the second body portion being on the        opposite side of the joint from the first body portion;    -   a connector joining the first support portion and the second        support portion;    -   a transducer connected to the lever arms such that torsional        forces are measured by the transducer; and    -   an output device operably connected to the transducer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an embodiment of an orthosis mounted around theknee of a patient.

FIG. 2 is a fragmentary, perspective view of the orthosis of FIG. 1removed from the patient.

FIG. 3 is a side view of an alternative embodiment of an orthosis with acord-based fastener using pulleys.

FIG. 4 is a side view of an embodiment of an orthosis with rigid shellsupport portions and an articulating hinge integrated with the supportportions.

FIG. 5 is a side view of an embodiment of an orthosis with a rigid shellsupport portions and a hinge connected to the frame elements.

FIG. 6 is a front view of an orthosis around the knee of a patient,where the orthosis has protuberances to resist motion of the orthosisduring exercises.

FIG. 7 is a side view of an orthosis around the knee of a patient, wherethe orthosis has binding straps to hold the orthosis in place duringexercises.

FIG. 8 is a rear view of a first gripping element in the orthosis ofFIG. 7.

FIG. 9 is a rear view of a second gripping element of the orthosis ofFIG. 7.

FIG. 10 is a perspective view of an orthosis around the knee of apatient, where the orthosis is attached to a belt to help hold theorthosis in place during exercises and activities such as walking.

FIG. 11A is a front view of a high friction sleeve worn around the kneeover which an exercise orthosis can be placed.

FIG. 11B is a front view of a high friction undergarment worn by apatient, where an exercise orthosis around the knee of the patient lieson top of a portion of the undergarment.

FIG. 12 is a side view of an orthosis secured with cross straps behindthe fold of the knee.

FIG. 13 is a fragmentary, top view of an instrumented intermediarysegment secured to the patient with pins using features of an externalfixator.

FIG. 14 is a fragmentary, top view of an alternative embodiment of aninstrumented intermediary segment secured to the patient with pins usingfeatures of an external fixator.

FIG. 15 is a sectional view of an embodiment of a resistance applicatortaken through the middle of the resistance applicator.

FIG. 16 is a sectional view of the resistance applicator of FIG. 15taken along lines 16—16 of FIG. 13.

FIG. 17 is a top view of a housing of the resistance applicator of FIG.15.

FIG. 18 is a sectional view of the housing of FIG. 17 taken along line18—18, where the lock pin has been removed.

FIG. 19 is a side view of a first lock pin of the housing of FIG. 17.

FIG. 20 is a side view of a second lock pin of the housing of FIG. 17.

FIG. 21 is a top view of a crank of the resistance applicator of FIG.15.

FIG. 22 is a sectional view of the crank of FIG. 21 taken along line22—22.

FIG. 23 is a sectional view of the crank of FIG. 21 taken along line23—23.

FIG. 24A is a top view of a crank ring of the resistance applicator ofFIG. 15.

FIG. 24B is a top view of a housing ring of the resistance applicator ofFIG. 15.

FIG. 25 is a perspective view of a compression spring of the resistanceapplicator of FIG. 15.

FIG. 26 is a bottom view of a knob of the resistance applicator of FIG.15.

FIG. 27 is a fragmentary, side view of the knob of FIG. 26, where aportion of the grip of the knob has been removed.

FIG. 28 is a top view of a bearing unit of the resistance applicator ofFIG. 15.

FIG. 29 is a sectional view of the bearing unit of FIG. 28 taken alongline 29—29 of FIG. 28.

FIG. 30 is a side view of a hinge suitable for use with the resistanceapplicator of FIG. 15.

FIG. 31 is a sectional view of the hinge of FIG. 30 taken along line31—31.

FIG. 32 is an exploded, perspective view of the hinge of FIG. 30.

FIG. 33 is side view of a stop pin useful with the hinge of FIG. 30.

FIG. 34 is a side view of a barrel bolt used for securing the hinge ofFIG. 30.

FIG. 35 is a fragmentary perspective view of a manual, hinge lockrelease.

FIG. 36 is a side view of a dual axis hinge suitable for use withresistance applicator of FIG. 15.

FIG. 37 is a side view of a proximal arm of the dual axis hinge of FIG.36.

FIG. 38 is a side view of a distal arm of the dual axis hinge of FIG.36.

FIG. 39 is a side view of a control ring of the dual axis hinge of FIG.36.

FIG. 40 is a side view of an inner plate of the dual axis hinge of FIG.36.

FIG. 41 is a side view of a resistance ring of the dual axis hinge ofFIG. 36.

FIG. 42 is a schematic illustration of possible division of componentsof the controller between placement on the orthosis and placement in aseparate portable unit.

FIG. 43 is a schematic diagram indicating components used in theamplification and balancing of the strain measurement.

FIG. 44 is a circuit diagram of one embodiment of a summing amplifieruseful as a component in the diagram of FIG. 43.

FIG. 45 is a flow diagram outlining the process for calibrating thestrain measurements.

FIG. 46 is a front, perspective view of a condyle sensor placed aroundthe knee of a patient.

FIG. 47 is a front view of an instrumented abduction/adductionexerciser.

FIG. 48 is a front view of an alternative embodiment of an instrumentedabduction/adduction exerciser.

FIG. 49 is a top view of an instrumented therapeutic cord.

FIG. 50A is a fragmentary, top view of a cuff used with an instrumentedtherapeutic cord.

FIG. 50B is a fragmentary, top view of a therapeutic cord with aninstrumented attachment.

FIG. 51 is a perspective view of a scale modified for use in theperformance of closed chain exercises.

FIG. 52 is a perspective view of a patient performing closed chainexercises with an exercise orthosis around the knee and using a scale ofFIG. 51.

FIG. 53 is a perspective view of two sensors located within a room, thesensors being useful for the performance of closed chain exercises.

FIG. 54 is a plot of range of motion exercises as measured with anorthosis of the invention.

FIG. 55 is a side view of a proprioception brace for performingcoordinated proprioception exercises with two limbs.

FIG. 56 is a plot of static closed chain exercises as measured with anorthosis of the invention.

FIG. 57 is a plot of dynamic closed chain exercises performed with anorthosis of the invention.

FIG. 58 is a flow diagram showing one embodiment of contingentintervention operation of the controller.

FIG. 59 is a schematic depiction of a computer screen window prompting ahealth care professional at a monitor station to select exercisesroutines.

FIG. 60 is a schematic depiction of a computer screen window depictingthe entry of exercise time parameters into the monitor station.

FIG. 61 is a schematic depiction of a computer screen window depictingthe entry of isometric exercise parameters into the monitor station.

FIG. 62 is a schematic depiction of a computer screen window depictingthe entry of range of motion exercise parameters into the monitorstation.

FIG. 63 is a schematic depiction of a computer screen window depictingthe entry of proprioception exercise parameters into the monitorstation.

FIG. 64 is a schematic depiction of a computer screen window depictingthe entry of isometric exercise shape parameters into the monitorstation.

FIG. 65 is a schematic depiction of a computer screen window requestingentry of an instruction related to the plot of downloaded exercise data.

FIG. 66 is a schematic depiction of the plot of raw data on theperformance of isometric exercises on a monitor station screen.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Orthoses can be used effectively to speed the rehabilitation of aninjured and/or weakened joint of a patient. In particular, an orthosiscan include a microprocessor to monitor and assist with the performanceof exercises. The microprocessor can also track the patient'sperformance and provide a means of reporting the performance to acentral collecting station or a health care professional. Importantfeatures have been identified that provide for efficient use of amicroprocessor monitored orthosis. By simplifying the use of arehabilitation orthosis through microprocessor instruction to thepatient as well as simplifying and improving monitoring of theexercises, accessibility to useful levels of rehabilitative exercise isgreatly enhanced. Some of the improved features can be used effectivelyin improved orthoses even without having microprocessor control.

Relevant orthosis fit around the joint of a patient, i.e., flexiblyconnected body portions. The orthosis can be designed to fit around anyjoint or series of joints including, for example, the knee, wrist,ankle, hip, elbow, shoulder, spine/back. Generally, the orthosisincludes a plurality of support portions connected by a hinge orcomparable connection. At least one support portion fits on one bodyportion on one side of a joint, while one or more other support portionsfit on a second body portion on the other side of the joint. The hingecan have a conventional design or one of the improved designs describedbelow. One or more support portions can be secured to the patient withthe use of an external fixator or other similar attachment approach.

Relevant orthoses can be used to assist with one or more rehabilitationprocedures. In particular, the orthosis preferably is useful to monitorthe performance of isometric exercises. Isometric exercises generallycan be performed relatively early in the rehabilitation of an injuredand/or weakened joint. In other preferred embodiments, the orthosis alsocan monitor the performance of range-of-motion exercises, proprioceptionexercises, isotonic exercises and/or closed chain exercises. Similarly,the orthosis can be designed to apply and monitor selective pressure toreduce forces applied to worn components of joints.

Some preferred embodiments include an additional component to providefor closed chain exercises when used with the joint supportingcomponent. Closed chain exercises involve muscular motion againstresistance to mimic natural motions or to provide balanced stresses tothe joint. Closed chain exercises can be contrasted with open chainexercises where a limb or the like is moved or stressed in space withoutany resistance against the motion other than perhaps the weight of thelimb itself. Closed chain exercise may provide more balanced exercise ofthe various muscle groups within a patient's limb or trunk. The closedchain component may or may not be physically connected with the jointsupporting orthosis components.

A strain sensor or strain gauge can be used to make measurements ofisometric exercises by measuring stress within the orthosis. Severaldesign features of the controller can be used to obtain useful strainmeasurements using relatively inexpensive hardware. These features aredescribed below.

The coordination of the exercise routine preferably is handled by amicroprocessor based controller that assists by prompting the patientfor the performance of an exercise routine and by monitoring theroutine. Generally, the controller is programmed with a target exerciseroutine selected by a health care professional. The controller assiststhe patient with the performance of the exercise by providing immediatefeedback with respect to evaluating the performance of the exercisesrelative to the target routine. The controller may store selectedinformation on the patient's performance of the exercises. Thisinformation can be downloaded for evaluation of compliance andperformance by a health care professional.

Alternative instrumented exercise devices include an instrumentedabduction/adduction exerciser and an instrumented therapeutic resistance(stretch) cord. These instrumented exercise devices can be used alone orin combination with an instrumented orthosis. Instrumentation of theseexercise devices provides for the monitoring and evaluation processesused with the instrumented orthosis.

1. Orthosis Construction

A relevant orthosis includes a joint support component, one or moretransducers, a control unit and, optionally, additional treatmentcomponent or components. Generally, the entire orthosis is portable inthe sense that the joint support component can be supported completelyby the corresponding body portions of the patient while the patient ismobile. Thus, the orthosis like a cast or the like is ambulatory, i.e.,carried by the patient during their activities. Any additional treatmentcomponents may or may not be physically connected with joint supportcomponent. The joint support component includes support portions joinedby a flexible connection or hinge.

A relevant orthosis generally includes, at least, one support portionattached on opposite side of the joint. The one or more support portionson one side of a joint are connected to the one or more support portionson the other side of the joint by a flexible connection. The flexibleconnection preferably is selectively flexible such that the flexibleconnection can be locked in a particular configuration. Of course, asuitable orthosis can cover more than a single joint, especially with aback orthosis. Nevertheless, elements can be identified as supportportions if by no other feature than being the last on either end of aset of articulating elements comprising the orthosis. The supportportions can have a variety of structures.

FIGS. 1 and 2 display one embodiment of an orthosis or brace 100 shownon a patient 102. Orthosis 100 includes support portions 104, 106connected by hinges 108, 110. The hinges can be mechanical,electromechanical or a combination thereof, as described further below.Support portion 104 includes a left frame member 120 and a right framemember 122 connected by flexible straps 124, 126.

Frame members 120, 122 generally are constructed from rigid materialssuch as steel, aluminum, other metals or alloys, fiberglass, composites,other similar materials, or combinations thereof. Flexible straps 124,126 preferably are adjustable such that the support portion 104 can befit to the patient. Adjustment of flexible straps 124, 126 can beperformed with hook and loop fasteners or any of a variety of otherfasteners including conventional fasteners. Flexible straps 124, 126 canbe replaced in alternative embodiments by sheets of fabric or the likewhich can be adjusted with hook and loop fasteners or other fastenersincluding conventional fasteners. Similarly, support portion 106includes a left frame member 140 and a right frame member 142 connectedby flexible straps 144, 146.

Support portions 104, 106 can include connections 148 for attachment toContinuous Passive Motion (CPM) devices, for example, on frame members120, 122, 140 and 142. Any of a variety of possible connections can beused that can transfer the force from the CPM device to the frame of theorthosis without damaging the orthosis. Suitable connections can be madewith any of a variety of releasable fasteners such as snaps, clips,pivots and the like. CPM devices are passive in the sense that motorsare used to flex joints. CPM devices can be useful in combination withan isometric exercise device since CPM devices can flex the joint over aparticular range of motion when the muscles have not yet healedsufficiently to perform comparable motions actively. The correspondingCPM machine would have the appropriate component of the connector forattachment to the orthosis. The CPM machine can be connected to thecontroller for orthosis 100. The controller can be used to control themotor speed and the like. The connection can be by way of a RS232connection, infrared connection, radio connection or the like.

Another alternative embodiment for replacing straps 124, 126 is shown inFIG. 3. A cord based adjustable fastener includes cords 160 windingbetween pulleys 162. Pulleys 162 can be covered with pulley covers 164.Cords 160 extend to handles 166. Handles 166 include hooks that attachto corresponding loop sheets 168 on fabric covers 170 that wrap partlyaround the corresponding body portion. Selected placement of the handlewith the hook and look fastener provides for a desired degree ofconstriction of the orthosis. The configuration of the hook and loopfasteners can be reversed with the loop associated with handles 164.Instead of using a handle to manually tighten or loosen the cord, amotor can be used to adjust the tension. Such a motorized, cord basedadjustment was described for use in a back brace in U.S. Pat. Nos.5,226,874 and 5,346,461, to Heinz et al., both of which are incorporatedherein by reference.

In an alternative embodiment of the orthosis 200, support portions 202,204 involve extended elements that fit the appropriate body portion, asshown in FIG. 4. Support portions 202, 204 generally are rigid and canbe constructed from a variety of materials. Preferred materials for theconstruction of support portions 202, 204 include, for example, moldedplastic shells, plaster, heat moldable thermoplastics, water-activatedfiberglass, heat shrink plastic and other cast forming materials.Support portions 202, 204 can be premolded in various sizes such that aparticular size is selected based on measurements of the patient.Alternatively, support portions 202, 204 can be constructed to fit aparticular patient. These custom molded support portions are molded tofit the body portions of the particular patient by a trained physicianor technician.

As shown in FIG. 4, support portions 202, 204 are connected by anarticulating hinge 206. Articulating hinge 206 can be made withresilient collapsible materials such as a bendable straw, slidingsections that can slide past each other to articulate, or other similarconstructions. Sliding sections can be locked relative to one another byway of clamps 208 attached to slots 209 defining a range of motion,where the clamps are tightened manually with wing nuts or the like , orelectronically with solenoids or the like. Referring to FIG. 5, in analternative embodiment support portions 202, 204 are connected withright frame elements 210, 212. Right frame elements 210, 212 areconnected by a right hinge 214. Comparable left frame elements and lefthinge on located on the opposite side of the patient's joint.

Right frame elements 210, 212 and the corresponding left frame elementscan be molded into the support portions 202, 204 when the supportportions are formed. In some preferred embodiments, sheaths 220, 222 aremolded into support portions 202, 204. Right frame elements 210, 212lock into sheaths 220, 222 such that right frame elements 210, 212 areheld firm relative to support portions 202, 204. For example, the sheathcan include a flange that allows a series of ridges to pass in a singledirection such that the frame element fits into the sheath but cannot beremoved. Similar lock elements are used plastic ties. Alternatively, areversible locking mechanism can be used, for example, where a lock pinor the like is inserted through the sheath and into the frame element.

Right frame elements 210, 212 can be disengaged from sheaths 220, 222either by disengaging a locking mechanism or by destroying the sheath220, 222. Sheath 220, 222 can be constructed from an inexpensive butdurable polymer. Thus, frame elements 210, 212 and hinge 214 can bereused in another orthosis. Comparable attachments would be used tosecure the left side of the support portions. Right hinge 214, rightframe elements 210, 212, sheaths 220, 222 can be placed into a kit.Generally, the kit would further include the corresponding left elementsand/or a strain sensor and controller, as described below. The kitpreferably would be placed within a single package although multiplepackages can be used if desired.

In preferred embodiments, the orthosis includes one or more strainsensors. The strain sensors are useful for the performance andmonitoring of isometric exercises with a selectively flexibleconnection/hinge in a locked position. Also, the strain sensor is usefulfor the measurement of forces during isotonic exercises. The strainsensors generally are located on a rigid element that is under stresswhen torque is applied to the selectively flexible connection/hinge.Thus, the preferred locations for the strain sensors depend on theparticular construction of the orthosis. Referring to FIG. 2, strainsensors 230 are attached to frame members 140, 142. Strain sensors 230can be connected to controller 232 (FIG. 1) by way of wires 234.Alternatively, strain sensors can be connected to controller 232 by wayof some form of telemetry. Referring to FIG. 4, strain sensor 230 isattached to support portion 204.

When forces are applied by the patient against the orthosis, theorthosis tends to change position relative to the patient's joint. Thisshifting reduces the effectiveness of exercises being performed with theorthosis and may necessitate realignment of the orthosis for proper fit.The orthosis can be designed to reduce or eliminate this shifting.

A first approach to prevent a knee orthosis from slipping duringexercise is to construct the orthosis with indentations 250, 252 in thefemur supracondylar area just above the knee, as shown schematically inFIG. 6. Preferably, the orthosis is instrumented. To further improve thecontact of the orthosis with the patient, a two sided adhesive pad canbe applied to the patient, such as at indentations 250, 252. In thisembodiment, the indentations or formed off of frame elements 254, 256projecting above hinges 258, 260. Similar indentations can be used withother orthosis constructions and with orthoses designed for other jointssuch that the orthosis grips the underlying bone structure.

Referring to FIGS. 7-9, an alternative solution involves the use ofadditional securing cuffs 270 and/or 271. Securing cuffs 270, 271 aredesigned to be tightened more during exercise routines to help securethe orthosis relative to the joint. Cuff 270 includes a gripping element272. The under side of gripping element 272 to be placed against the legabove the knee preferably has a semiquadrangular shape such that whentightened, gripping element 272 applies pressure above the kneecap andpushes on the knee without pushing on the vasculature and lymphaticdrainage posteriorly. Cuff 271 includes gripping elements 273 placed onboth sides of the shin just above the ankle. Cuff 271 steadies theorthosis from below. Cuffs 270, 271 can be tightened with a variety offasteners including hook and loop fasteners and can include a pulley orquick rachet system similar to that shown in FIG. 3. Alternatively, thecuffs can be tightened using a lever with a fulcrum in the middle and astrap on the bottom such that the strap tightens when the lever is movedfrom one side of the fulcrum to the other.

Another approach to securing the orthosis involves securing the orthosis274 to a belt 275 by way of one or more straps 276. In preferredembodiments, straps 276 and belt 275 provide a path for electricalcommunication between electronic elements 277 and electronic elements278 on belt 275. Straps 276 can be secured using hook and loopfasteners, hooks or any other reasonable fastener.

Still another approach involves increasing the friction of the surfacecontacting the orthosis or part of the orthosis. For example, in FIG.11A a polymer sleeve 279 is worn around the knee and the orthosis wouldbe placed over sleeve 279. Sleeve 279 can be made from a sheet or meshof neoprene. The orthosis is secured to sleeve 279 using hook and loopfasteners, snaps or ribbing or the like for frictional securing.Similarly, as shown in FIG. 11B underwear 280 with high frictionextending down to cover all or part of the area over which an orthosisis placed helps to reduce movement of the orthosis.

Referring to FIG. 12, another approach to securing the orthosis involvesthe placement of crossed straps 281 behind the knee. Straps 281 applyforces that tend to maintain straps 281 in the fold of the knee.Furthermore, for a knee orthosis, the orthosis can end with a heel cup282 or stirrup with a strap 283 or the like around the foot to hold thebottom of the orthosis around the heel of the foot. The knee orthosis issecured to heel cup 282 with appropriate connectors to fix the positionof the hinge at the knee, as shown in FIG. 3. Similar anchor-typestructures can be placed on orthoses covering other body parts to resistshifting of the orthosis.

With any of these approaches for inhibiting orthosis motion during use,the method preferably distributes the restraining forces sufficientlysuch that no portion of the skin is subject to excessive pressures thatcould bruise the skin as well as damage or interfere with neural orcirculatory functions.

The instrumented orthoses described above involve an external frameworkthat surrounds a patient's joint. The orthoses are appropriatelydesigned to secure comfortably the orthosis around the joint and toresist movement of the orthosis when forces are applied to the orthosis.As an alternative to the use of an instrumented orthosis surrounding therespective body portions, the instrumented orthosis can include one ormore rigid attachments to the patient. These alternative forms of theorthosis use structures such as external fixators or the like forattachment. External fixators have been used to secure broken bones andto reduce fractures by attaching an external, rigid frame to a patient'sbone with pins. When integrated into the instrumented orthoses describedherein, the structure of an external fixator involves the attachment ofthe external frame to one or more hinge elements. Suitable hingeelements for use in orthoses with an external fixator structure are thesame as those hinge elements that are suitable in orthoses with a purelyexternal framework.

A first embodiment of an instrumented orthosis secured with features ofan external fixator is depicted in FIG. 13. Frame elements 284, 285 areconnected with a connector 286. Connector 286 can be a flexibleconnector such as a hinge, or a rigid connection that holds the firstsupport portion and the second support portion at a fixed angle. Ifconnector 286 is a hinge, the hinge can include fasteners for theattachment of a removable resistance element. Alternatively, the hingecan include an intrinsic resistance element. The resistance elementpreferably proved adjustable resistance such that a desired resistanceto the rotation of the hinge can be selected.

Clamps 287 are attached to each frame element 284, 285. As shown in FIG.13, two clamps 287 are secured to each frame element 284, 285, althoughone or more than two clamps can be secured to each frame element, ifdesired. Each clamp 284, 285 is further secured to a pin 288. Pins 288intrude into the patient and are inserted into the bone, as shown inFIG. 13 with phantom lines. Generally, the clamps and frame elements canbe positioned to obtain a desired orientation with respect to the bone.Additional frame elements can be used to obtain a desired orientationbetween the frame elements secured with pins and the hinge elements.

A variety of clamp and frame element structures can be used. Suitableclamps are described further in U.S. Pat. No. 5,674,221 to Hein et al.,entitled “External Fixator With Improved Clamp And Methods For Use,”incorporated herein by reference, and in U.S. Pat. No. 5,891,144 to Mataet al., entitled “External Fixator,” incorporated herein by reference.Generally, transducers that are connected to controller 232 are attachedto an orthosis with external fixator structures in a comparable way aswith orthoses having purely external frameworks.

The external fixator generally includes one or more transducers 299.Transducer 299 can be a strain sensor such that strain within the leverarms can be measured. Alternatively, transducer 299 can be a positionsensor if the connector is a hinge. The position sensor measures therelative orientation of the lever arms. Additional transducers 299 canbe included to measure deforming bone/tissue forces. For example, astrain sensor can be added to the pins, such that strain within the pinsis measured.

An alternative embodiment of an instrumented orthosis with externalfixator type connections is shown in FIG. 14. In this embodiment, frameelements 289, 290 are placed on either side of the body part. Clamps 291are secured to frame elements 289, 290 and to pins 292 that pass intothe patient's bone, as shown in phantom lines in FIG. 14. Frame elements289, 290 are connected to frame elements 293, 294 with hinge elements295, 296. Frame elements 293, 294 are secured on the patient with straps297. Pins 292 help to prevent motion of the entire orthosis duringexercise. Various features of the orthosis embodiments in FIGS. 13 and14 can be combined as desired.

Similar structures can be used for attachment to the spine. In thesesystems, pins can be replaced with spinal hooks or screws. Suitablespinal attachment systems are described further in U.S. Pat. No.5,281,222 to Allard et al., entitled “Spinal Implant System,”incorporated herein by reference.

As described above with respect to FIGS. 1-5, the flexible connectioncan be a hinge, a set of articulating elements or the like. In preferredembodiments, the flexible connection includes a position sensor suchthat the relative orientation of the connection can be measured andmonitored by the controller 232. U.S. Pat. No. 5,052,375, to Stark etal. entitled “Instrumented Orthopedic Restraining Device and Method ofUse,” incorporated herein by reference, discloses the use of apotentiometer-like mechanism used as a position sensor. Other suitableposition sensors can be used. Position sensing is useful for theevaluation of range-of-motion exercises and other comparable exercises.

Furthermore, preferred flexible connections can be locked in selectedorientations. If the flexible connection can be locked, isometricexercises can be performed at the locked orientation. The lock can bereleased and relocked at a new orientation to perform additionalexercises at the new location. A couple of locking mechanisms aredescribed in U.S. Pat. No. 5,052,375, supra. Similarly, it is useful forthe flexible connection to be able to apply selected amounts ofresistance to rotation. If selected amounts of resistance can beapplied, the orthosis can be used more effectively for the performanceof isotonic exercises. Copending U.S. patent application Ser. No.08/442,945 to Stark, entitled “An Orthopedic Device Supporting Two orMore Treatment Systems and Associated Methods,” incorporated herein byreference, describes the electronic selection of a desired amount ofmechanical resistance using the control unit.

While electronic control of the rotational resistance in the flexibleconnection has advantages, cost and design simplicity favors a purelymechanical hinge. The strain sensor readings can be accuratelycalibrated to reflect the forces applied to move the hinge against asetting on the mechanical resistance applicator. Thus, the controllercan be used to monitor the isotonic exercises even though the resistanceis not electronically controlled. In this respect, a resistanceapplicator 300 (FIGS. 15-29) has been designed for use with a hinge. Theresistance applicator can be made integral with the hinge, but inpreferred embodiments resistance unit 300 can be separated from thehinge such that no resistance is applied to the hinge when resistance isnot desired. Resistance applicator 300 is designed to amplify smallchanges in the resistance that correlate with easily made changes in theposition of a knob.

Referring to FIG. 15, a cross section through the center of anembodiment of resistance applicator 300 is shown. Similarly, FIG. 16displays a cross section taken along lines 16—16 of FIG. 15. Resistanceapplicator 300 includes housing 304, a crank 306, a compressionstructure 308, knob 310, bearing unit 312, washer 314 and spacers 316.

Referring to 17-19, housing 304 includes base 326 and lock pins 328,330. Lock pins 328, 330 provide releasable connection for attachment ofresistance applicator 300 to a hinge. Alternative locking approaches canbe used for the attachment of the friction applicator to the hinge. Base326 includes threaded hole 332 for engaging knob 310 and threaded holes334, 336 for engaging lock pins 328, 330, respectively. Base 326 furtherincludes protrusion 338 for engaging compression structure 308. Lock pin328 includes threads 340 for engaging threaded hole 334, and lock pin330 includes threads 342 for engaging threaded hole 336. Alternatively,lock pins 328, 330 can be welded or the like to base 326.

Referring to FIGS. 21-23, crank 306 has a central portion 350 and an armportion 352. Center portion 350 includes notches 354 for engagingcompression structure 308. Arm portion 352 includes ridge 356 and pads358. Ridge 356 and pads 358 engage frame member 122 (FIGS. 1 and 2) orcomparable frame member of an orthosis, such that rotation of the hingeof the orthosis rotates crank 306 relative to housing 304.

Compression structure 308 provides for small changes in the resistancedue to changes in the distance between washer 314 and housing 304 asknob 310 is rotated, thus amplifying resistance changes by way of theknob. Compression structure 308 generally produces friction as a resultof shear forces within compression structure 308 due to relative motionof housing 304 and crank 306. In the embodiment in FIGS. 15-29,compression structure 308 includes alternating crank discs 370 (FIG.24A) and housing discs 372 (FIG. 24B) to form a multiple clutch plate.Compression structure 308 further includes a compression spring 373.

Crank discs 370 include protrusions 374 that engage notches 354 suchthat crank discs 370 rotate with crank 306. Housing discs 372 have acentral hole 376 shaped to engage protrusion 338 in housing 304 suchthat housing discs 372 rotate with housing 304. Compression spring 373includes an elastic protruding section 378 with a central hole 379.Compression spring 373 can be replaced with an spring washer or thelike. In one preferred embodiment, compression structure includes 7housing discs 372 and 6 crank discs 370 in an alternating layers. Otherquantities of crank discs 370 and housing discs 372 can be used asdesired.

Referring to FIGS. 26-27, knob 310 includes a grip handle 380 and athreaded shaft 382 with threads and diameter suitable for engaging thethreads of threaded hole 332 in housing 304. Referring to FIGS. 28-29,bearing unit 312 includes a ring of ball bearings 384 in a bearing case386. Bearing unit 312 can be replaced with other bearing structures orother friction reducing approaches such as hydro bearings.

Washer 314 has a suitable inner diameter such that threaded shaft 382can pass through the inner diameter but bearing unit 312 cannot pass.Washer 314 has an outer diameter such that washer 314 rests on centerportion 350 of crank 306 covering the opening to compression unit 308between housing 304 and crank 306. Two optional spacers 316 preferablyare located with one on each side of compression unit 308. Spacers 316have the shape of a washer but with a suitably larger inner diameter andsmaller outer diameter than washer 314 such that spacers 316 fit withinthe cavity between crank 306 and housing 304 holding compressionstructures 30B.

The primary components of the resistance applicator 300 preferably aremade from metals and/or alloys. Aluminum alloys and stainless steel aresuitable metals for the construction of housing and crank components.Rigid polymers can be used in place of metals for the housing and crankelements. The spacers preferably are made of brass. The housing discpreferably is made from spring steel, and the crank disc preferably ismade from spring tempered phosphor bronze. The bearing case can be madefrom Nylon®.

Resistance applicator 300 is designed to attach to a hinge such thathousing 304 moves with a frame member attached to one side of the hingewhile crank 306 moves with a frame member attached to the other side ofthe hinge. Thus, rotation of the hinge results in rotation of housing304 relative to crank 306. Tightening of knob 310 presses washer 314down onto compression unit 308. Housing rings 372 and crank rings 370rotate relative to each other when housing 304 moves relative to crank306. Increasing the pressure on compression unit 308 results inincreased resistance in the rotation of housing 304 relative to crank306 because of friction between housing rings 372 and crank rings 370.Increasing the number of housing rings 372 and/or crank rings 370increases the amount of resistance. This design provides for sensitiveadjustment of rotational resistance provided by resistance applicator300 by rotation of knob 310. Housing rings 372 and crank rings 370 canhave non-uniform thickness or non-uniform shape such that the degree ofresistance varies as a function of rotational angle.

A particular embodiment of a left hinge 400 for use with resistanceapplicator 300 is shown in FIGS. 30-32. This hinge has a constructionthat provides for particularly easy release of the lock by a patientwith one hand. The orientation of the hinge is measured by a positionsensor to assist the patient in resetting the lock at a desiredorientation. A right hinge would be the mirror image of the hinge inFIGS. 30-32.

Hinge 400 includes a outer plate 402, washer 404, locking unit 406, ringlever 408, electrical resistance disc 410 and inner plate 412. Outerplate 402 is connected to a frame member 418. Strain sensor 230 can beattached to frame member 418. Outer plate 402 and inner plate 412include concentric stop holes 420, bolt holes 422, connection holes 424and slot 426. The corresponding holes are aligned between left outerplate 402 and inner plate 412.

One or two stop pins 430 (FIG. 33) can be placed through two alignedstop holes 420 in outer plate 402 and inner plate 412 to define limitsor end stops of hinge rotation. Barrel bolts 432 (FIG. 34) including amale member 434 and a female member 436 or other fastener are securedthrough bolt holes 422 to hold hinge 400 together. Lock pins 328, 330 ofresistance applicator 300 can be secured through connection holes 424 toreleasably secure resistance applicator 300 in an operable position withrespect to hinge 400. Electrical resistance disc 410 rests within ahollow 43B within inner plate 412. Electrical resistance disc 410 makeselectrical contact with wire 440.

Locking unit 406 includes control disc 446, slider 448, slider spring450 and lock-out latch 452. Control disc 446 included a slit 454 inwhich slider 448 slides. Slider 448 has a groove 456 and an indentation458 with a catch 460. Lock-out latch 452 has a knob 462 and a bar 464.Bar 464 slides within slots 426 and can fit within groove 456 to holdslider 448 in a depressed, unlocked, position.

Ring lever 408 is connected with a frame member 470. Ring lever 408 hasan opening 472 with a diameter slightly larger than the diameter ofcontrol disc 446 such that control disc 446 can fit within opening 472.Control disc 446 preferably has a thickness slightly larger than ringlever 408. A set of concentric, notches 474 are located around the edgeof opening 472 of ring lever 408. Catch 460 of slider 44.8 fits withinthe notches 474 to lock the hinge at a particular orientation whenslider 448 is in an extended position. Depressing slider 448 against theforce of spring 450 disengages catch 460 from one of the notches 474such that hinge 400 is free to rotate within the bounds establishes byany stop pins 430. Ring lever 408 includes an electrical contact 476 setwithin a hole 478 that contacts electrical resistance disc 410.Electrical contact 476 is connected by wire 480 to controller 232 oralternative resistance meter. Washer 404 can be placed between outerplate 402 and control disc 446.

Outer plate 402, inner plate 412, ring lever 408, control ring 446,lock-out latch 452 and slider 448 preferably are made from rigid,durable materials. In particular, outer plate 402 and inner plate 412are preferably made from an aluminum alloy, and ring lever 408, controlring 446, lock-out slide 452 and slider 448 preferably are made fromstainless steel. Spring 450 generally would be made from resilient steelor the like. Washer 404 and stop pin 430 generally are made frompolytetrafluoroethylene or the like. Electrical resistance disc 410 canbe made from circuit board material with a resistance elementscreen-printed on its surface.

Frame members 418 and 470 extend to opposite sides of the hinge suchthat movement of frame member 418 relative to frame member 470 involvesrotation of hinge 400. When hinge 400 rotates, outer ring 402 and innerring 412 rotate relative to ring lever 408. Outer ring 402, inner ring412 and control disc 446 are held fixed with respect to each other byway of bolts passing through bolt holes 422. The orientation of hinge400 is locked unless slider 448 is depressed such that catch 460 iswithdrawn from notches 472. Lock-out slide 452 can hold slider 448 inthe depressed, unlocked position. The position of ring lever 408relative to inner ring 412 can be measured by way of the position ofelectrical contact 476 along electrical resistance disc 410. Therelative position of electrical contact 476 along electrical resistancedisc 410 provides a variable electrical resistance useful forposition/orientation sensing.

It may be convenient to provide for release of a hinge with a remotecontrol. U.S. Pat. No. 5,052,375 provides for the release of the hingeusing a command from the control unit. It may be desirable to have asimple mechanical remote release. A simple photographic shutter release490 (FIG. 35) can be adapted for this purpose. Shutter release 490 canbe screwed at threaded tip 492 into hinge 400 at threaded hole 494 incontrol ring 446 (FIG. 32). Pressing plunger 496 advances cable 498.When shutter release 490 is screwed into hinge 400 advancing cable 498depresses slider 448 thereby unlocking hinge 400. Rotating knob 500causes plunger 496 to spring back to its extended position withdrawingcable 498 and locking hinge 400 as slider 448 extends such that catch460 engages a notch 472. Alternative designs for mounting of a manualhinge release involve pulling a plunger that in turn pulls slider 448such that the lock is disengaged and such that releasing the plungerreestablishes the hinge lock.

Certain joints such as the knee are cams that do not involve rotationabout a single axis. A biaxial hinge can be used to more closelyapproximate the motion of the joint cam. A biaxial hinge 510generalizing on the structure of hinge 400 is shown in FIGS. 36-41.Biaxial hinge 510 includes a proximal arm 512 and a distal arm 514.Proximal arm 512 includes teeth 516 which engage teeth 518 on distal arm514. Proximal arm 512 further includes lock notches 530 and anelectrical contact 532 for position (orientation) sensing. Control ring534 operates similarly to control ring 446 in hinge 400 to control thelocking/unlocking of the hinge. Inner plate 536 includes an indentation538 for securing electrical resistance disc 540. Electrical resistancedisc 540 provides for variable electrical resistance according to theorientation of the hinge due to the relative position of the electricalcontact 532 with respect to electrical resistance disc 540.

In simplified embodiments, controller 232 may just include analogcircuits and a suitable display. In preferred embodiments, controller232 includes a digital processor to provide a more sophisticatedinterface with the patient and to preform more involved monitoringfunctions. The digital processor preferably is a microprocessor. Thedigital processor can be programmed in any of a variety of computerlanguages including, for example, basic, assembler, C, C++ and the like.Preferably, controller 232 is portable, which in this context means thatthe controller is small enough to be held in the hand of a patient. Morepreferably, controller 232 is small enough to be placed in a standardshirt pocket.

A preferred microprocessor based controller 232 has several subsystemsincluding a power supply such as a nine volt battery, a transducer biascircuit such as described below, A/D converters, a microprocessor, realtime clock, RAM and non-volatile storage such as FLASH or EEPROM, agraphic display such as a 64×128 pixel LCD display with a correspondingdriver, keypad, audible or tactile feedback device, data link totransducer, and RS232 standard output for serial connection or modemaccess.

In one particular embodiment, the microprocessor is a MotorolaMC68HC11A1FN 8-bit microcontroller with built-in deep sleep shutdownmode for power conservation between active events, a programmable serialinterface and an 8-channel, 8-bit A/D converter. In this embodiment,controller 232 can provide analog multiplexing and A/D conversion for upto 8 analog input signals over a voltage range from 0.0 to +5.0 volts.For example, three of the channels can be devoted to provide signalconditioning for up to three strain sensors, and three of the channelscan be devoted to providing signal conditioning for up to three position(angle) sensors. The remaining two input channels then can be used foradditional treatment devices.

The controller module memory is partitioned into FLASH, SRAM and EEPROM.Each section is independently addressable. In one particular embodiment,FLASH is 128 K words, and EEPROM is 32K words with 8-bits (1 byte) perword. A 16K portion of SRAM is used for memory management. The EEPROMsupports in-circuit reprogramming by way of the microcontroller serialchannel for code updates. The SRAM has battery backup, and FLASHprovides non-volatile storage of recorded data during times when themicroprocessor is not powered. The real time clock also is batterypowered to allow time keeping to continue when the microcontrollercircuitry is off. The real time clock is capable of generating periodicinterrupts at a programmable rate to power switching circuitry toactivate the microcontroller during an alert mode of operation.

The RS-232 interface consists of three conductor (TxD, RxD and GND) jacktype connector with a mechanical switch to automatically switch power onto all on-board electronics when the plug is inserted. The baud rate ofthe interface is programmable with standard rates such as 9600 and19200. A suitable display is a Hantronix HGS13Y or Densitron™ LE3328 LCDwith Hitachi HD61202 and HD61203 LCD controller chip sets. The displaycan be run with a five volt supply that can be separate or not from thepower supply for the rest of controller 232. In this embodiment, a fourkey keypad is interfaced with the microcontroller.

All of the components of controller 232 can be placed on the orthosis orin a separate case. The components of controller 232 can be integratedinto a single package or physically partitioned into portions mounted onthe orthosis frame and/or portions placed into one or more small cases.This is shown schematically in FIG. 42, where connections between theOrthosis side to the portable unit(s) side indicates that a connectioncan be made by a hard wire connection or telemetry. Generally, thecomponents are not duplicated such that various combinations can be madefollowing a selected path through the chart. In one preferredembodiment, controller 232 is mounted in a single case that isreleasably attached to the orthosis frame so that the case can becarried on the frame and removed when desired to read the display moreeasily. In an alternative preferred embodiment, the display andcorresponding drivers can be mounted in one case that can be moved foreasier viewing while the remaining components are attached to the frameof the orthosis. The display can be interfaced with the remainingportions of the controller with a wire, by radio, communication or byinfrared communication. A video card with an RF modulator to convertingbroad band video into analog NTSC signals in controller 232 can beattached to a television set rather than to a graphic display. Use of atelevision provides better viewing as well as conserves battery powersince the display alternatively would be consuming significant amountsof battery power. An alternative output for persons who arevision-impaired is to provide audible feedback, either in the form ofrecognizable sounds that change when a target is reached, throughvariations in pitch or volume, or by a voice synthesizer that speaks tothe patient such as “Push Harder,” “Good,” or “Now rest for a moment.”

Controller 232 preferably stores a software program that manages the useof the device for patient rehabilitation. The software can provide foralerting the patient to scheduled times for the performance of exercisesusing audible and/or vibratory signals. Controller 232 preferablyprovides instructions on the exercises as well as feedback andreinforcement messages to the patient. Further details on the operationof the controller are provided below.

Stored information relating to the patient's performance of exercisesgenerally is downloaded to the supervising health care professional atspecified intervals. The download of the information can be performed ina variety of ways. If the patient goes to the office of the health careprofessional, controller 232 can be directly connected to the monitorstation/computer using the RS232 port or other port using suitableprotocols including standard protocols. Alternatively, controller 232can be attached to a modem by way of the RS232 port or other suitableport. Since with certain embodiments the file sizes are relativelysmall, a single chip, 9 volt supply Rockwell® 2400 baud modem can beused. Controller 232 can be in radio communication with a monitorstation. Controller 232 then would include a radio transmitter and,optionally, a receiver. Radio communication with a monitor station isdescribed further in copending U.S. patent applications to Stark et al.,Ser. No. 08/389,680 entitled “Communication System For an InstrumentedOrthopedic Restraining Device and Methods Therefore” and Ser. No.08/804,950 entitled “Local Monitoring System For an InstrumentedOrthopedic Restraining Device and Methods Therefore,”both of which areincorporated herein by reference. The display or television setsimilarly can be in communication with controller 232 by way of radiotransmissions or infrared communication such that a wire attachment isnot necessary.

In order for the value of electrical resistance associated with a strainsensor to be useable as a measure of applied stress during isometricexercises, the values must be referenced to a “null” valve approximatelycorresponding to a value when no strain is applied to the orthosis. Thenull value can be set by a manual adjustment performed by the healthcare professional or by the patient. The “null” value, however, ispreferably established automatically without the need for calibration bythe user. Furthermore, the variations in the resistance due the strainsensor preferably are converted into a voltage value that is amplifiedto make efficient use of an analog-to-digital (A/D) converter with aspecified number of binary digits.

An approach for performing this calibration is outlined schematically inthe block diagram of FIG. 43. A summing amplifier 600 amplifies a signalbased on the resistance of the strain sensor relative to an input signalfrom a digital-to-analog (D/A) converter 602. The signal from summingamplifier 600 goes to an A/D converter 604. The signal from A/Dconverter 604 goes to processor (CPU) 606. Processor 606 evaluateswhether the signal from the A/D converter is within a desired range andadjusts the signal to D/A converter, if appropriate to bring the signalfrom the A/D converter to be within a specified range. An NationalSemiconductor® 8 bit, 8 channel D/A chip can be used. Processor 606further uses the signal for monitoring the exercise routine anddisplaying the results, or sends the signal to a different processor toperform these functions.

An embodiment of summing amplifier 610 is shown in FIG. 44. Amplifier610 is a two stage amplifier including a first amplifier circuit 612 anda second amplifier circuit 614. First amplifier circuit 612 includesstrain sensor resistance R_(SG) 616 connected to ground 618, a referencevoltage V_(REF), source voltage V_(CC) and D/A reference voltageV_(D/A). First amplifier circuit 612 further includes amplifier 634,capacitor C₃₆ 626 and resistors R₁₃ 628, R₁₅ 630, R₁₆ 632 and R₁₉ 634.First amplifier circuit 612 outputs a voltage V₀₁ to second amplifiercircuit 614.

Second amplifier circuit 614 includes amplifier 638 and resisters R₁₇640, R₁₈ 642, R₂₁ 644 and R₂₁₀ 646. Resister R₂₁₀ is further connectedto ground. Second amplifier circuit 614 outputs voltage V₀₂ and currenti₀₂ to A/D converter 604.

The output voltage for summing amplifier 610 can be calculated to be:V₀₂ = X₁V_(Ref) − X₂V_(CC) − X₃V_(D/A),  where$X_{1} = {\left\lbrack {\left( \frac{R_{17} + R_{18}}{R_{17}} \right) - \frac{R_{18}R_{21}R_{210}}{{\left( R_{17} \right)^{2}\left( {R_{21} + R_{210}} \right)} + {R_{17}R_{21}R_{210}}}} \right\rbrack \times {\quad{{\left\lbrack {\frac{{R_{13}\left( {R_{15} + R_{16}} \right)} + {R_{15}R_{16}}}{R_{13}R_{15}} - {\frac{R_{16}}{R_{13}}\frac{R_{19}R_{strain}}{{R_{strain}\left( {R_{13} + R_{14}} \right)}R_{13}R_{14}}}} \right\rbrack X_{2}} = {{\left( {\left( \frac{R_{17} + R_{18}}{R_{17}} \right) - \left( \frac{R_{18}R_{21}R_{210}}{{\left( R_{12} \right)^{2}\left( {R_{21} + R_{210}} \right)} + {R_{17}R_{21}R_{210}}} \right)} \right) \times \left( {\frac{R_{16}R_{strain}}{{R_{strain}\left( {R_{13} + R_{19}} \right)} + {R_{13}R_{19}}} + \frac{R_{18}R_{210}}{{R_{17}\left( {R_{21} + R_{210}} \right)} + {R_{21}R_{210}}}} \right)X_{3}} = {\left( \frac{R_{16}}{R_{15}} \right)\left( {\left( \frac{R_{17} + R_{18}}{R_{17}} \right) - \left( \frac{R_{19}R_{21}R_{210}}{{\left( R_{12} \right)^{2}\left( {R_{21} + R_{210}} \right)} + {R_{17}R_{210}R_{21}}} \right)} \right)}}}}}$For use with a general purpose, 350 ohm strain gauge/sensor, suitableaccuracy is obtained using resistors with a 1% tolerance except asindicated below. Suitable strain gauges/sensors are available fromVishay Micromeasurements Group (Raleigh, N.C.) (e.g., type 125AD, partnumber EK-XX-125AD-350 with dual copper pads), or JP Technologies (SanBernardino, Calif.). The input voltage V_(CC) can be set to 5.0V±0.1 andV_(Ref) can be set to 2.5V±0.1%. Then, one suitable set of values forthe resistors and capacitors are R₁₃=1 K Ω, R₁₅=150K Ω, R₁₆=100K Ω,R₁₇=1.5K Ω, R₁₈=32K Ω, R₁₉=350K Ω±0.1%, R₂₁=2.5K Ω, R₂₁₀=2.5K Ω,R_(SG)=350 Ω±0.3% and C₃₆=0.01 μF. With these values of components thechange in strain gauge resistance to move the output voltage from about0 V to about 5V is in the range from 1.2515 Ω to 1.3568 Ω. The summingamplifier overall provides a nominal gain of about 2300 with an accuracyof about +/−0.125 ft-lbs.

A flow chart 660 outlining the performance of the calibration is shownin FIG. 45. The calibration is initiated 662 by setting the D/A outputto the summing amplifier 600 to a midrange value assuming that no stressis being applied to the orthosis by the patient. Then, the A/D input isread 664 by the CPU 606. The error in the digitized strain measurementis calculated 666 based on a desired set-point given the parameters ofthe summing amplifier 600 and the properties of the A/D converter 604.The error is compared 668 with acceptable tolerance values. If the erroris within tolerance values, the calibration is terminated 670. If theerror is outside of tolerance values, a new value of output from the D/Aconverter is calculated 672 to bring the error of the output from theA/D converter to within tolerance values. The value of the output fromthe D/A converter is set 674 to the adjusted value. Then, the input fromthe A/D converter is read 664 again and steps 664-668 are repeated untilthe error is within tolerance values.

Additional treatment units can be combined with the exercise orthosis toassist with the rehabilitation of a joint. For example, the controller232 can coordinate isometric and/or isotonic exercise treatments alongwith energy propagating transducer treatments. Exercise/transducercombined treatment approaches are described generally in copending U.S.patent application Ser. No. 08/442,945 to Stark, entitled “An OrthopedicDevice Supporting Two or More Treatment Systems and Associated Methods,”incorporated herein by reference. Energy propagating transducer basedtreatments include, for example, ultrasonic treatments, pulsedelectromagnetic treatments and electrical conductance treatments.

In addition, a treatment device for alleviating pain due toosteoarthritis can be monitored by controller 232 or comparable controlunit. The osteoarthritis treatment device could be effectively usedalone or combined with an exercise orthosis. Joins often wear unevenly.This results in pain due to bone on bone contact where cartilage hasworn away. A support can be placed around the joint to shift thestresses to the less worn portions of the joint thus alleviating pain.

Referring to FIG. 46, an appropriate osteoarthritis support 680 for aknee is shown. Osteoarthritis support 680 includes a restraint 682 and aforce applicator 684. Knees often wear excessively on the medial (inner)side of the knee. Applying force on the lateral (outer) side of the kneeshift stress from the medial to the lateral side of the knee.Occasionally knees wear excessively on the lateral side, in which casethe support can be adjusted accordingly. Force applicator 684 can be apad, a bladder or similar device. Force applicator 684 should distributethe force over a reasonable area so that the skin is not damaged and nosignificant circulatory or neural functions are interrupted. Restraint682 can be any suitable strap or the like such that the forces arebalanced in a suitable location displaced from the joint.

The amount of a force applied to the joint preferably is measured toavoid the application of excessive force and to monitor compliance. Theapplied lateral forces can be measured using a pressure sensor or strainsensor 686 in or on force applicator 684 and/or using a strain sensor688 on restraint 682. Pressure sensors/strain sensors 686, 688 can beconnected to the controller 232 by way of wires 690.

Suitable strain sensors were described above. Pressure sensor 686 can beany reasonable type. A variety of suitable pressure sensors arecommercially available. Preferred pressure sensors include the MPX,series of pressure sensors manufactured by Motorola because of theirlinear output and small size. Other suitable pressure sensors use silveroxide ink surfaces separated by a dielectric material or piezoelectricmaterials that produce a voltage when stressed. Suitable pressuresensors include strain sensors attached to the surface of a bladdersince the surface strain is a function of the pressure in the bladder.

Osteoarthritis support 680 to alleviate osteoarthritis can bebeneficially used with an exercise orthosis. The performance ofisometric or isotonic exercises stimulates the secretion of naturallubricating fluids within the joint. Thus, the support can alleviate thepain sufficiently to perform the exercises, which lead to further painalleviation due to the secretion of lubricating fluids. The combinationof the exercise orthosis and osteoarthritis support 680 can provideconsiderable improvement in the condition of the patient. Osteoarthritissupport 680 can be easily redesigned for other joints or to alleviatepain associated with unusual wearing of a particular joint.

Other instrumented exercise units can be used in conjunction with theorthosis/brace using a single controller 232 or multiple controllers, oralone as an alternative to the orthosis/brace. One such alternativeexercise unit is an abduction/adduction exercise device. A firstembodiment of an instrumented abduction/adduction exerciser 700 is shownin FIG. 47. Exerciser 700 is used in conjunction with an orthosis 702.

Abduction/adduction exerciser 700 includes two lever arms 704, 706.Lever arms 704, 706 are joined at hinge 708. Lever arm 706 of exerciser700 releasably attaches to hinge 710 of orthosis 702 with connector 712.Lever arm 704 is attached to a padded cuff 714 that can be securedaround the patient's leg with a hook-and-loop fastener or the like.

Generally, hinge 708 can be released and locked at a selectedorientation. Hinge 708 is locked at an orientation for the performanceof isometric exercises. Alternatively, hinge 708 freely rotates, andlever arms 704, 706 are held at a nominal position by spring 716 and canbe moved toward each other with the application of force. The amount offorce needed to move lever arms 704, 706 can be varied by suitableselection of spring 716.

Instrumented abduction/adduction exerciser 700 includes a strain sensor718 or the like to measure stresses within exerciser 700. Strain sensor718 is connected to controller 232 or to a separate control unit. Thus,when the patient flexes or stresses and releases exerciser 700, as partof an exercise routine, the compressive forces applied by the patientcan be measured, prompted and monitored similarly to forces applies toan orthosis.

In this particular embodiment, abduction/adduction exerciser 700 isdesigned to be flexed by a patient's legs. Straightforward modificationscan be used to design a comparable exerciser for use with other flexiblebody parts, such as an exerciser flexed by movement of a patient's armrelative to their body trunk.

Referring to FIG. 48, an alternative embodiment of anabduction/adduction exerciser 730 includes lever arms 732, 734. Leverarms 732, 734 are connected at variable resistance hinge 736. Variableresistance can be applied, for example, with the mechanical resistanceapplicator described above with respect to FIGS. 15-29. Alternatively,electronically controlled variable resistance hinges described above canbe used. Lever arms 732, 734 are attached to cuffs 738, 740 that aredesigned to engage the patients leg or other suitable body part.

Abduction/adduction exerciser 730 includes suitable transducers, such asa strain sensor 742 and/or a position sensor 744 connected to hinge 736.Transducers 742, 744 are connected to controller 232 or to anothersuitable control unit/display. Measurements from the transducers can beused to monitor, prompt and evaluate the exercises by the patient.

Another alternative instrumented exercise device is an instrumentedtherapeutic cord, i.e., bands or tubes. The un-instrumented versions ofthese devices are sold under the tradenames of Thera-Band®,MediCordz®and StretchCordz®. Instrumented therapeutic cords provide aversatile, low cost exercise alternative, which can be used alone or incombination with an instrumented orthosis, as described herein. Theunifying theme of these devices is the presence of an elastic cord thatprovides resistance against motion by the patient.

A embodiment of an instrumented therapeutic cord 750 is depicted in FIG.49. Therapeutic cord 750 includes two handles/clamps 752, 754 connectedto elastic cord 756. One or more the handles/clamps can be replaced witha cuff 758, as shown in FIG. 50A. Cuff 758 can be designed to fit arounda patient's waist or limb, or a table leg or other rigid object for theperformance of certain exercises. Referring to FIG. 50B, one or morehandles/clamps can be replaced with a fastener 760 such as a hook thatconnects to a fixed handle 762. A variety of approaches can be used tofasten the instrumented therapeutic cord to a fixed object for theperformance of exercises. Additional handles/clamps or cuffs can beused, as desired, for the performance of specific exercises.

Cord 756 is connected to a transducer 764 directly or indirectly by wayof a handle or the like. As shown in FIGS. 49 and 50A, the transducer764 is attached between cord 764 and handle 754 or cuff 758, althoughtransducer 764 can be attached to other portions of cord 764. Iftransducer 764 is attached indirectly, the transducer should be attachedto a handle or the like that experiences strain when forces are appliedto cord 756, such that in either embodiment, the forces measured by thetransducer are functions of the forces applied to the cord. Transducer764 can be a strain sensor or stretch sensor. Suitable stretch sensorsare commercially available based on piezoelectric transducers, molecular[?], grid resistance transducers or the like. The transducer can beattached to a suitable substrate for mounting. Transducer 760 can beconnected to controller 232 or other suitable control unit.

To perform exercises with an instrumented therapeutic cord, one of thehandles/clamps 752, 754 can be attached to an immovable object such as adoor knob of a closed door. The patient then stretches the cord, usingthe other handle/clamp 752, 754, a cuff 758 or the like, with a hand,foot, limb or other body part to exercise the corresponding muscles.Alternatively, the patient stretches cord 756 while contacting thetherapeutic cord 750 at two or more points, such as two handles/clamps752, 754. A large variety of exercises can be performed by appropriatelyselecting the arrangement of the therapeutic cord.

To adjust the exertion required in the exercises with the therapeuticcord, therapeutic cords are commercially available with differentamounts of resistance. If desired, the different levels of resistancecan be color coded by the color of the cord, the handle or a portion ofthe cord. Each cord with different levels of resistance need to becalibrated such that the transducer reading can be correlated with theexerted forces. Controller 232 can be programmed with separate look-uptables for each level of resistance. If the resistance level of the cordis input into the controller, the controller can make the suitablecorrelation.

For the performance of closed chain exercises, a body portion pushesagainst an essentially immovable surface. The surface can be a floor, awall, a table top or the like. In order to monitor the forces beingapplied, a sensor is used that is placed between the body part and thesurface. For example, in FIG. 1 orthosis 100 includes a foot support800. Foot support 800 includes a connecting member 802 and a pressuresensor 804.

As an alternative to using a foot support connected to an orthosissurrounding a joint, the force sensor can be a separate unit. Inparticular, foot support 800 can be replaced by a scale 810 or the like,as shown in FIGS. 51 and 52. Scale 810 preferably includes a port 812for connection with a wire 814 to controller 232. Alternatively, scale810 can include a radio transmitter 816 that transmits measurements tocontroller 232.

If closed chain exercises are to be performed with joints other than theknee, a suitable force sensor can be used. For example, a elbow can beexercised pushing with a hand against a pad sensor 818 on a table or padsensor 820 against a wall, as shown in FIG. 53. These sensors can beconnected to the controller in the same way as scale 810.

A plurality of force sensors can be used for the performance of closedchain exercises. The controller can instruct the patient to vary therespective forces on the two force sensors. For example, twoinstrumented scales can be used with one scale having forces appliedwith an injured leg and the second scale having forces applied with anuninjured leg. the patient can be instructed to switch forces betweenthe two legs at a prescribed rate.

A monitor station can be used by the health care professional to planand monitor the treatment of the patient. Any computer can be used toperform this function. In particular, Windows® based systems aresuitable although Unix®, Macintosh®, LINUX®, html-based or JAVA® systemscould also be used. The monitor station should have suitable ports forconnection with the controller 232.

With any of the additional treatment units including an osteoarthritissupport, an abduction/adduction exerciser, a therapeutic cord and aclosed chain exercise monitor, as with the instrumented orthosis itself,the display can be used to present various summaries and statistics tothe patient. Suitable statistics to be displayed include, for example,exercise times, repetitions, calories expended, and curves where thearea under the curve represents work exerted by the patient during anexercise cycle. Similarly, the variance between a target goal and actualperformance during an exercise can be displayed.

2. Orthosis Control

The controllers described above preferably are programmed under thecontrol of an appropriate health care professional. Selection of thedesired program is described further below. In this section, themonitoring of selected types of treatments using a microprocessor basedcontroller is described.

In one preferred embodiment, the controller has four modes of operation:OFF, STANDBY, ALERT and FULL ON. In the OFF mode, primary and backupbattery power are removed, and no operations are taking place in thecontroller. In the STANDBY mode, no primary battery power is online, andbackup battery power is used to maintain the real time clock and SRAM.Back-up power can be supplied by a coin cell or the like. STANDBYmode-is generally used while the primary battery is being replaced orrecharged.

In ALERT mode, the real time clock produces a signal at programmed,periodic intervals to activate all on-board electronic components.ALERT-ACTIVE submode has all circuits active. Exercises are generallyperformed during the ALERT-ACTIVE mode. In ALERT-SLEEP submode, only thereal time clock and SRAM memory remain active. ALERT-SLEEP mode is thestandard mode of operation between exercise prompts. To allow switchingbetween submodes, primary and backup battery power should be availableduring the ALERT mode. A beeper function can be used to prompt thepatient that an exercise time has been reached.

FULL-ON mode primarily is used during programming and data transferoperations. All on-board electronics and the display are active. FULL-ONmode can be activated automatically when an interface cable isconnected.

In a preferred embodiment, the controller can prompt and monitor theperformance of isometric exercises, range of motion exercises,proprioception exercises and/or isotonic exercises. When the health careprofessional programs the controller, the desired exercises from thisset are selected along with the associated parameters and timingconditions for the selected exercises. Also, the controller preferablycan store two or more sets of exercise routines that can be used indifferent time intervals relative to the start of rehabilitation. Inother words, after a first set of exercise routines have been used for acertain period of time, the controller selects a second, generally moredifficult, set of exercises for the patient to perform. These exercisescan be performed for any selected joint.

Preferably, the controller prompts the patient at the time forperformance of the selected exercises. In some embodiments, the patientpresses a key when they are ready to proceed. The display on the monitorcan graphically show the patient's motions with suitable coordinates forthe particular exercise and compare them with a target, if suitable. Thecontroller can store all of the data points or averages over a set ofexercises performed over a period of time. In some embodiments, onebutton of the controller is a pain button that the patient hits whenthey feel pain during the exercises. Pain data points from the pressingof the button can be correlated with time, position and activity so thatfurther information for evaluation of the exercise routine is available.

To perform the isometric exercises, the hinge/flexible connector isadjusted to a particular angle. If a manual hinge is used, the hinge ismanually, adjusted. The controller may instruct the patient if the hingeis set at the desired angle. At the correct angle, the patient appliesstress against the fixed hinge in one direction or the other. Thecontroller instructs the patient if the applied stresses are withintolerance values of a target value. The controller preferably promptsthe patient regarding the timing of the exercises, including therepetition rate and the amount of time to hold an applied stress. Afterthe selected number of repetitions are performed the exercises areterminated or a new angle of the hinge is selected. The process isrepeated until exercises are performed at all of the desired angles.

Improvement in the joint benefits from attention to achieving adesirable range-of-motion (ROM). The ROM can be monitored using theorthosis with a suitable position sensing hinge/flexible connector, asdescribed above. The hinge is set to allow rotation, at least over aportion of the possible rotation range. The performance of ROM exercisesis plotted schematically in FIG. 54 using polar coordinates. The angularcoordinate represents the angle of the hinge in the orthosis, and theradial coordinate depicts time. Four routines are depicted. Theseroutines could be used for four weeks of exercises or four othersuitable time periods. Each higher number routine represents motion overan increased angular range.

Proprioception in this context refers to the patient's sense of positionin space, such as the bend of a particular joint. This seeming innateknowledge is a learned phenomenon involving a complex interaction ofnerve sensations from sensors that are processed and combined withfeedback and correction. A joint has dozens of single-celled measurementsensors: Golgi tendon organs, Paninian-like receptors, Ruffinicorpuscles and the like. The brain and spinal cord process theinformation from these cellular sensors. When a joint is damaged, dozensof sensors may be permanently lost. For example, the anterior cruciateligament of a knee has over 60 sensor/receptor cells may be lost whenthe ligament tears. The body makes up for lost receptors by recruitingnew sensor information from adjacent places. A new pathway and analysismust be relearned by the nervous system. With a properly designedorthosis this process can be accelerated and enhanced.

In one embodiment, the controller display prompts an action through agraphic display, for example, to get a ball back into a circle, and thepatient must react quickly, reflexively with the rehabilitating joint inthe orthosis to move the ball on the screen. The position of the ball onthe screen is correlated with the position of the joint by way of theposition sensor in the orthosis operably connected to the controller. Bychanging the position of the joint, e.g. knee, the patient can move theball back into the circle or to another target of some kind. The patienthas a limited amount of time to perform the action. As the patientprogresses, generally she is given less and less time to respond untilthe joint has completed recovery. For a joint located on a limb,recovery can be evaluated relative to the joint on the contralaterallimb. This exercise can be embedded into a wide variety of game-typeenvironments, where the input comes from the orthosis rather than ajoystick or the like. These exercises improve cooperation andcoordination. A similar game format can be used to perform isometricexercises where the amount of strain measured by the strain sensor isused to move the cursor.

Because proprioception involves the whole body, a collateral, i.e.,uninjured, limb may have, significant impact on proprioceptionperformance of the injured limb. It may be advantageous to train thelimbs, such as an injured and uninjured leg, together. A simple bracecan be placed on the uninjured limb. A suitable proprioception brace 780is shown in FIG. 55. Brace 780 includes an upper frame member 782 and alower frame member 784 connected by a hinge 786. Suitable straps 788 orthe like can be used to secure brace 780 to the uninjured limb. Straps788 can attach with hook-and-loop fasteners or other simple fasteningsystem.

Hinge 786 preferably includes a position sensor 790 that can beconnected to controller 232. In one application, the patient wearing aninstrumented orthosis on the injured limb (e.g., leg) and aproprioception brace on the uninjured limb (e.g., leg) can be instructedto shift forces from one limb to the other with specific timingindicated by motion of an object shown on the screen of the controller.For example, the patient may be instructed to shift weight from one legto the other in a series of closed chain, i.e., weight bearing,proprioception exercises.

Isotonic exercises are similar to the range-of-motion exercises exceptthat selected resistance is provided in the hinge/flexible connection.Resistance is provided by a manual unit such as resistance unit 300above or by an electrical resistance hinge actuated by the controller.In any case, a desired amount of resistance is set manually orautomatically. The joint is then flexed over a prescribedrange-of-motion. Controller can monitor the degree of flexing of thejoint using the position sensor and the amount of forces applied duringthe flexing using the strain sensor. The strain sensor can be calibratedsuch that a strain reading can be matched with a corresponding torqueapplied to the hinge. If the instrumented orthosis includes both astrain sensor and a position sensor, the outputs relating to the twodifferent transducers can be displayed with the two dimensional motionon the display of a cursor or the like, with the position in therespective dimensions being determined by the reading of a correspondingtransducer.

As noted above, the controller can be attached to a variety ofadditional devices, such as closed chain exercise units, energypropagating transducers, condyle sensors and the like, to assist withtreatment. Generally, the monitoring of the operation of theseadditional units can be performed with the controller in astraightforward manner. The use of the closed chain exercise units isdescribed in more detail.

The performance of closed chain exercises can be performed in either astatic/isometric mode or a dynamic isotonic mode. In the static mode,the patient flexes the knee or other joint to the desired angle and thenleans against an opposing surface to apply a desired amount of force.The hinge can be locked or unlocked during the exercises. Afterperforming a programmed number of repetitions, the patient is instructedto move the joint to a different orientation. At the new orientation,the patient again applies force according to a pre-programmed targetamount of force. The process is repeated until the exercises areperformed at all the selected orientations. Again, the exercise can beincorporated into a variety of game formats, such as a slalom skier,basketball free throws, a road race course, a simple moving bar graph,“Pong,” or the like.

This process is depicted schematically in FIG. 56 for the performance ofclosed chain exercises at 7 different angles. The plot in FIG. 56 is inpolar coordinates where the angular coordinate represents the rotationabout the hinge and where the radial coordinate is the force applied tothe closed chain force sensor. The angle and force can be monitored bythe controller and stored for future evaluation. Similarly, the angleand force can be displayed to provide immediate feedback to the patientduring the exercises.

To perform dynamic closed chain exercises, the hinge of the orthosis isfree to rotate during the exercises. The orthosis is first brought to aparticular orientation. Then, a desired amount of force is applied atthat orientation for a period of time. While the force is appliedagainst the closed chain force sensor, the hinge is rotated to anotherselected orientation. At the new orientation, the amount of forceapplied is changed and held for a particular period of time. Again, theorientation is changed while the force is being applied. The process isrepeated according to the programming in the controller. Dynamic closedchain exercises creates small but useful and controlled amounts of jointshear.

The procedure for a single dynamic closed chain exercise routine isdepicted schematically in FIG. 57 in polar coordinates. The angularcoordinate corresponds to the angular orientation of the hinge of theorthosis and the radial coordinate is the amount of force applied to theclosed chain force sensor. The arrows indicate changes in applied forcesor orientations performed by the patient while the points indicate stoppoints where forces and orientation are held fixed for a period of time.The entire exercise can be repeated with the same parameters ordifferent parameters according to a prescribed program. Also, thechanges in orientation can be reversed such that the patient moves thehinge from larger angles to smaller angles.

The control unit can be programmed to accept other input from thepatient. In particular, inquiries can be directed to the patient at thestart of an exercise routine, at the end of an exercise routine or atother times. The answers are stored for downloading to a health careprofessional along with suitable information regarding the performanceof programmed exercises. Additional information on the types ofinquiries are described further below.

As part of the monitoring operation, the controller preferably,continuously monitors the performance of an exercise to preventdifficulties. On embodiment of this contingency processing is outlinedin FIG. 58. The patient is signaled 902 to initiate the performance ofexercises. The performance of the exercises are evaluated to determineif exercises are being performed 904. If not, a counter is evaluated todetermine if the warning limit has been reached 906. If the warninglimit not, the reminder or signal to initiate the exercises is repeated908, and the evaluation if exercises are being performed 904 isrepeated. If the limit on number of warnings has been reached, it isevaluated if the limit of non-activity periods has been reached 910. Ifthe limit of non-activity periods has not been reached, the controllerenters sleep mode 912. If the limit of non-activity periods has beenreached, the patient is instructed 914 to call the doctor.

If exercises have been started at step 904, the transducer parametersare evaluated to determine if the exercises are being performed 916within specified parameters. If they are within tolerance ranges, it isevaluated if the exercises are complete 918. If the exercises arecomplete, the controller enters sleep mode 920. If the exercises are notcomplete, the evaluation of the performance 916 of the exercises isrepeated.

If the exercises are not being performed within tolerance values, theexercises are evaluated to determine if excessive force is being applied922. If excessive force is being applied, a sound warning is given 924,and the evaluation of the exercises 916 is repeated. If excessive forceis not being applied, it is determined 926 if the patient was previouslywarned a maximum number of time that the exercise is not being performedcorrectly. If the maximum number of warning has not been given, thepatient is notified 928 again, and the evaluation 916 is continued. Ifthe patient has been warned a predetermined number of times previously,the exercise parameters are evaluated to determine 930 if they are atprogrammed limits. If not, the parameters are modified 932, and theevaluation 916 is repeated. If the parameters are at preprogrammedlimits, it is determined 934 if an error warning has previously beengiven that the parameters are at their limits. If the error warning wasnot previously given, the warning is given 936, and the monitoring 916is repeated. If the warning was previously given, the patient isinstructed 938 to call the doctor, and the controller enter a sleep mode940.

Periodically, the information stored by the processor is downloaded to ahealth care professional. Various methods for downloading theinformation were described above. In principle, the controller can storeall of the information about the performance of particular sets ofexercise routines and download all of this information for analysis.Alternatively, the controller can perform some initial data analysis toreduce the amount of data that must be stored and transferred. Thus, rawor analyzed data can be transferred.

The preliminary analysis, if any, performed by the controller caninclude grouping and/or averaging of groups of exercises over certainperiods of time and/or performed at particular times of the day. Thisanalysis can involve an evaluation of variation with the progress oftime to assist the health care professional evaluate whether the patientis making sufficient improvement and to evaluate whether the exerciseroutine programmed into the controller is appropriate. In oneembodiment, the controller downloads the date, time, number ofrepetitions of an exercise, force curves, range-of-motion end stopsachieved, number of hits in a proprioception game, and number of timesthe patient pushed the pain button.

3. Use of Orthosis

To reduce the chance of the patient injuring themselves using theorthoses described herein, the patient preferably is examined by atrained health care professional prior to using the orthosis. Uponevaluating the condition of the patient, the controller is programmedfor suitable exercises. In preferred embodiments, the monitor stationassists the health care professional (HCP) with the programming process.In particular, the monitor station can lead the programmer through a setof questions to design to type of exercise routine desired. Based on theanswers to the questions, the monitor station pieces together theprogram for the controller. Once the controller is connected to themonitor station by way of an RS 232 connection, a modem, connection, aradio connection, an IR connection or other suitable connection using anappropriate protocol, the program is downloaded into the controller.

Generally, the monitor station stores information on a particularpatient, so the HCP initially instructs the monitor station whether thepatient is a new patient or a continuing patient. Initial questionspreferably include patient's age within a set of ranges, patient's sex,joint involved, and type of injury.

In one preferred embodiment, the monitor leads the HCP through a seriesof screens to fill in information related to the performance ofexercises within up to five different time periods, as shown in FIGS.59-64. The HCP can indicate the number of days that each phase willlast. The parameters for each type of exercise to be performed in eachphase are then set, see FIGS. 60-64. The monitor can be programmed tosuggest exercise routines based on information entered about thepatient. The HCP can modify the suggested routines as desired.

Additional screens can be used to provide additional input regardingadditional treatment add ons and/or information regarding the controllerand the means for communicating with the controller. Once the HCP hascompleted the specification of the exercise routine, the controller isconnected to the monitor station and the controller is programmed withthe exercise routine.

At prescribed periods of time, information stored in the controllerregarding the performance of the exercises by the patient can bedownloaded into the monitor station. The time interval can bedetermined; based on the storage capacity of the controller, thesuitable length for evaluation of progress by HCP or other similarissues. The download of information from the controller to the monitorstation can be performed at the health care facility where the monitorstation is located or at a remote location. If performed at the healthcare facility, the information can be downloaded by direct hook up ofthe controller with the monitor station or through a modem, radioconnection, infrared connection or the like. Remote hook up can beperformed with a modem connection, radio communication or other longerrange connection including, for example, the internet.

Suitable analysis is performed of the data. for example, the downloadeddata on the exercises can be plotted in raw form or following some formof data averaging or selection. Examples are shown in FIGS. 65-66. Basedon an evaluation of the downloaded data, the HCP can maintain theexercise program in its initially programmed form or modify the exerciseprogram to account for unexpected developments. In preferredembodiments, the HCP can reprogram the controller remotely such that anydesired changes in the routine can be made without the patient needingto visit the health care facility.

To facilitate the monitoring function, real time telecommunication canbe performed such that information on the exercises can be received bythe health care professional as the exercises are being performed.Similarly, the patient and health care professional can exchangecommunications in real time. Real time telecommunications can involveteleconferencing or videoconferencing. In addition, the patient and/orhealth care professional can interface with a web site to access ormaintain data base information and or as a communication portal.Additional information on these remote monitoring approaches is providedin U.S. patent application Ser. No. 09/266,866 to Oyen et al., entitledREMOTE MONITORING OF AN INSTRUMENTED ORTHOSIS,” incorporated herein byreference.

One of several important functions of a microprocessor controlledorthosis is to monitor compliance with performance of exercises. Auseful adjunct to the compliance monitoring function can be achieved byperforming a psychological evaluation of the patient. The psychologicaltest can be used to evaluate the suitability of the programmed exercisesas well as indicate other potential problems with the healing processnot directly linked to the exercises.

A relatively simple form of the psychological test can involve questionsfor the patient prior to the performance of the exercises regarding thepatient's readiness to perform the exercises and after the exercisesregarding the usefulness of the exercises. The inquiries can take theform of selecting from a selection of a representative graphicalrepresentations, such as a happy face, a frowning face etc. A moresophisticated test can involve questions regarding pain being felt bythe patient. One systematic set of questions regarding pain have beendeveloped at McGill University and are known as the McGill PainQuestionnaire. The questions relate to the degree of pain, the locationof pain, changes in pain and the sensation of pain. The answers can bepresented as numerical values that are scored according to a prescribedformula. A further description of the McGill Pain Questionnaire isdescribed in R. Melzack, “The McGill Pain Questionnaire: MajorProperties and Scoring. Methods,” Pain 1:277-299 (1975), incorporatedherein by reference. The questionnaire can be updated and modified asappropriate.

The psychological test can be used as part of the evaluation of thepatient. In particular, the exercise routine can be modified in responsepartly to the to mental attitude of the patient to help assure furthercompliance with the exercises and to increase the comfort level of thepatient. The balance of all of these factors can lead to fasterrehabilitation of the patient. Additional description of the use ofpsychological evaluation as an adjunct to orthopedic treatment isprovided in U.S. patent application Ser. No. 09/339,071 to Stark et al.,entitled “REHABILITATIVE ORTHOSES,” incorporated herein by reference.

The embodiments described above are intended to be exemplary and notlimiting. Further embodiments are within the claims below. Although thepresent invention has been described with reference to preferredembodiments, workers skilled in the art will recognize that changes maybe made in form and detail without departing from the spirit and scopeof the invention.

1. A method of performing coordination exercises for neuromotortraining, the method comprising: flexing a first joint of a patient suchthat a cursor on a display moves to reach a target position on thedisplay at a selected, predetermined time, the motion of the cursorbeing correlated with the motion or strain of the joint by way of asensor in an ambulatory orthosis placed at the joint, the ambulatoryorthosis comprising a portable controller and a support portion thatfits around the joint such that the ambulatory orthosis is carried bythe patient during the flexing step, the controller comprising a digitalmicroprocessor.
 2. The method of claim 1 wherein the orthosis comprises:a first support portion that fits around a first body portion on a firstside of the joint; a second support portion that fits around a secondbody portion, the second body portion being on the opposite side of thejoint from the first body portion; a flexible connection connecting thefirst support portion and the second support portion; a position sensoroperably connected to the flexible connection such that the positionsensor detects the relative orientation of the first support portionswith respect to the second support portion.
 3. The method of claim 1wherein the cursor motion is correlated with the strain of a joint byway of a strain sensor.
 4. The method of claim 1 wherein the cursormoves in two dimensions with the motion in one dimension correspondingto output of a position sensor and motion in the other dimensioncorresponding to output of a strain sensor.
 5. The method of claim 1further comprising flexing a second joint to simultaneously vary thedisplay along with motion of the first joint, wherein variations in thedisplay due to motion of the second joint is determined by the output ofa position or strain sensor at the second joint.
 6. The method of claim5 wherein the sensors are operably connected to a portable controllercomprising a digital microprocessor, the digital microprocessorproviding a target for the flexing of the first and second joint on thedisplay.
 7. The method of claim 1 wherein the sensor is selected fromthe group consisting of a strain sensor and a position sensor.
 8. Anambulatory orthosis system comprising: a display, a support portion thatfits around a joint and is carried by the patient during activities anda sensor on the support portion, and a portable controller comprising adigital microprocessor, the controller being operably connected to thesensor, wherein the controller controls the display based on signalsfrom the sensor, and wherein the patient, flexing the joint, causes acursor movement on the display, in which the motion of the cursor iscorrelated with motion of the joint as detected by the sensor in thesupport portion when the support portion is associated with the joint ofthe patient.
 9. The ambulatory orthosis system of claim 8 wherein thedisplay is integral with the portable controller.
 10. The ambulatoryorthosis system of claim 8 wherein the display is part of a television.11. The ambulatory orthosis of claim 8 wherein the support portion hasan appropriate structure to fit around a patient's knee.
 12. Theambulatory orthosis of claim 8 wherein the support portion has anappropriate structure to fit around a patient's elbow.
 13. Theambulatory orthosis of claim 8 wherein the display provides a target tobe reached by the patient through their movement of the joint.
 14. Theambulatory orthosis of claim 8 wherein the sensor comprises a strainsensor.
 15. The ambulatory orthosis of claim 8 wherein the sensorcomprises a position sensor connected to a hinge.
 16. The ambulatoryorthosis of claim 8 wherein the orthosis comprises a binge.
 17. Anambulatory orthosis system comprising: a display, a support portion thatfits around a joint and is carried by the patient during activities anda sensor on the support portion, wherein the support portion comprises ahinge, and a portable controller comprising a digital microprocessor,the controller being operably connected to the sensor, wherein thecontroller controls the display based on signals from the sensor, andwherein the patient, flexing the joint, causes a cursor movement on thedisplay, in which the motion of the cursor is correlated with motion orstrain of the joint as detected by the sensor in the support portion isassociated with the joint of the patient.